解:net start mysql
解:net stop mysql
解:mysql -uroot -p
再在命令行中输入:mysql密码
解:show databases;(注:命令后必须跟上英文分号)
解:use 需要进入的数据库;(注:命令后必须跟上英文分号)
解:show tables;(注:命令后必须跟上英文分号)
解:create database demo1;(注:命令后必须跟上英文分号)
解:drop database demo1;(注:命令后必须跟上英文分号)
解:CREATE TABLE t_student(
id BIGINT PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(30),
age INT,
email VARCHAR(30)
)(注:每列需要英文逗号隔开,最后一列不需要)
解:DROP TABLE t_student
解:CREATE TABLE `order`(
id BIGINT PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(30),
age INT
)(注:每列需要英文逗号隔开,最后一列不需要。表名不能使用关键字,如果要使用需要反引号括起来)
解:DROP TABLE `order`(注:表名不能使用关键字,如果要使用需要反引号括起来)
CREATE TABLE t_student(
id BIGINT PRIMARY KEY AUTO_INCREMENT,
name VARCHAR(30),
age INT,
email VARCHAR(30)
)
解:INSERT INTO t_student(name,age,email)VALUES('张三',18,'[email protected]')
解:INSERT INTO t_student(name,age)VALUE('周七',22)
解:INSERT INTO t_student(name,age,email)
VALUES ('李四',19,'[email protected]'),('赵六',18,'[email protected]'),('王五',20,'[email protected]')
解:INSERT INTO t_student (name) SELECT name FROM t_student
解:DELETE FROM t_student WHERE id=6
解:UPDATE t_student SET name='赵匡胤' WHERE id=7
解:UPDATE t_student SET name='张三丰',age=140,email='zhangsanf@'
解:DELETE FROM t_student
CREATE TABLE `product` (
`id` bigint(20) NOT NULL AUTO_INCREMENT,
`productName` varchar(50) DEFAULT NULL,
`dir_id` bigint(20) DEFAULT NULL,
`salePrice` double(10,2) DEFAULT NULL,
`supplier` varchar(50) DEFAULT NULL,
`brand` varchar(50) DEFAULT NULL,
`cutoff` double(2,2) DEFAULT NULL,
`costPrice` double(10,2) DEFAULT NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=22 DEFAULT CHARSET=utf8;
INSERT INTO `product` VALUES ('1', '罗技M90', '3', '90.00', '罗技', '罗技', '0.50', '35.00');
INSERT INTO `product` VALUES ('2', '罗技M100', '3', '49.00', '罗技', '罗技', '0.90', '33.00');
INSERT INTO `product` VALUES ('3', '罗技M115', '3', '99.00', '罗技', '罗技', '0.60', '38.00');
INSERT INTO `product` VALUES ('4', '罗技M125', '3', '80.00', '罗技', '罗技', '0.90', '39.00');
INSERT INTO `product` VALUES ('5', '罗技木星轨迹球', '3', '182.00', '罗技', '罗技', '0.80', '80.00');
INSERT INTO `product` VALUES ('6', '罗技火星轨迹球', '3', '349.00', '罗技', '罗技', '0.87', '290.00');
INSERT INTO `product` VALUES ('7', '罗技G9X', '3', '680.00', '罗技', '罗技', '0.70', '470.00');
INSERT INTO `product` VALUES ('8', '罗技M215', '2', '89.00', '罗技', '罗技', '0.79', '30.00');
INSERT INTO `product` VALUES ('9', '罗技M305', '2', '119.00', '罗技', '罗技', '0.82', '48.00');
INSERT INTO `product` VALUES ('10', '罗技M310', '2', '135.00', '罗技', '罗技', '0.92', '69.80');
INSERT INTO `product` VALUES ('11', '罗技M505', '2', '148.00', '罗技', '罗技', '0.92', '72.00');
INSERT INTO `product` VALUES ('12', '罗技M555', '2', '275.00', '罗技', '罗技', '0.88', '140.00');
INSERT INTO `product` VALUES ('13', '罗技M905', '2', '458.00', '罗技', '罗技', '0.88', '270.00');
INSERT INTO `product` VALUES ('14', '罗技MX1100', '2', '550.00', '罗技', '罗技', '0.76', '300.00');
INSERT INTO `product` VALUES ('15', '罗技M950', '2', '678.00', '罗技', '罗技', '0.78', '320.00');
INSERT INTO `product` VALUES ('16', '罗技MX Air', '2', '1299.00', '罗技', '罗技', '0.72', '400.00');
INSERT INTO `product` VALUES ('17', '罗技G1', '4', '155.00', '罗技', '罗技', '0.80', '49.00');
INSERT INTO `product` VALUES ('18', '罗技G3', '4', '229.00', '罗技', '罗技', '0.77', '96.00');
INSERT INTO `product` VALUES ('19', '罗技G500', '4', '399.00', '罗技', '罗技', '0.88', '130.00');
INSERT INTO `product` VALUES ('20', '罗技G700', '4', '699.00', '罗技', '罗技', '0.79', '278.00');
INSERT INTO `product` VALUES ('21', '光盘', null, '10.00', '罗技', '罗技', '0.80', '2.00');
解:SELECT * FROM product
解:SELECT id,productName,salePrice FROM product
解:SELECT dir_id FROM product
解:SELECT id,productName,salePrice*cutoff FROM product
解:SELECT id,productName,costPrice*50 FROM product
解:SELECT id,productName,(costPrice+1)*50 FROM product
解:SELECT id,productName,(costPrice+1)*50 AS allPrice FROM product
解:SELECT DISTINCTdir_id FROM product
解:SELECT * FROM product WHERE salePrice=119
解:SELECT * FROM product productName='罗技G9X'
解:SELECT * FROM product WHERE productName!='罗技G9X'
解:SELECT * FROM product WHERE dir_id!=2
解:SELECT productName,salePrice FROM product WHERE salePrice<=200
解:SELECT id,productName,salePrice*cutoff FROM product WHERE salePrice*cutoff>=350
解:SELECT id,productName,salePrice FROM product WHERE salePrice>=300 AND salePrice<=400
解:SELECT id,productName dir_id FROM product WHERE dir_id=2 OR dir_id=4
解:SELECT id,productName,dir_id,salePrice,costPrice FROM product WHERE salePrice>=250 OR costPrice>=200
解:SELECT id,productName,salePrice FROM product WHERE salePrice BETWEEN 300 AND 400
解:SELECT id,productName,salePrice FROM product WHERE salePrice NOT BETWEEN 300 AND 400
解:SELECT id,productName,dir_id FROM product WHERE dir_id IN(2,4)
解:SELECT id,productName,dir_id FROM product WHERE dir_id NOT IN(2,4)
解:SELECT id,productName,dir_id FROM product WHERE dir_id IS NULL
解:SELECT id,productName FROM product WHERE productName LIKE '罗技M9_'
解:SELECT id,productName,dir_id,salePrice FROM product WHERE salePrice>=80 AND productName LIKE '%罗技M1__'